Flour sifter



A. L. ZUCK FLOUR SIFTER March 16, 1943.

Filed June 13, 1940 Patented Mar. 16, 1943 inist AUNTED STATES @fig/FICE FLOUR SIFTER Albert L. Zuck, Rockford, Ill., assignor to The Washburn Company, Worcestenltlass., a corporation of Massachusetts Application Junel, 1940, Serial No. 340,28

Claims. (Cl. 209-357) This invention relates to a new and improved flour sifter.

The sifter of my invention is of that type in which the sifting operation can be done with one hand,thus leaving the other hand of the'operator free to do Whatever other work is necessary at the same time. devised before but have not operated as easily -as desired, the designs not having provided the necessary mechanical advantage to insure easy operation of the agitator. It is therefore the prin- .vcipal object of my invention to provide'a flour rsifter in which the operating lever pivoted in the `handle has a push and pull connection with the agitator at a point fairly remote from its pivot, i ywhereby a good mechanical advantage is secured and the agitator canbe operated rapidlyto and.

fro with very light nger pressure on the lever.

rThere is, therefore, no likelihood of fatigue.

Other objects and advantages of the invention will appear in the course of the following description, in which reference is made to the accompanying drawing, wherein i Figurefl is a central vertical section through a flour sifter made inaccord'ance with my inven- ,g

tion;

Fig.: 2vv is a. horizontal section approxirnately 'in `the plane of the line 2-2 of Fig. 1, and

Fig. 3 is a vertical sectional detail on the Vline 3-3 of Fig. 1.

The same reference numerals are applied to corresponding-.parts throughout these views.

The sitter comprises a sheet metal casing .li of :cylindrical form, open at the top-and bottom, and

having anatV screen bottom 5 vsuitably secured-.at

its marginal edges in thelower end of the casing, as indicated at 6. The flouris sifted through the screen A5. and the sifting-'operation is facilitated by the oscillation of the agitator 'if relative to' its pivot 8'by means of a lever 9-pivoted in the' handle I0 at II. wherein an agitatoris oscillated orreciprocate'd by means ofv a lever movable relative tothe handle Sifters of this general type have beenl Generally speaking sifters of this type.

by the same hand gripping the handle for support of `'the sifter fhave been provided heretoforeV but invariably the operating connection between' the agitator. Theseobjections -have to a'largefextent been eliminated in the'sifter of my invention-by locating the pivot 8 for Ythe -agitator 1 approximately -removed from'the handle Il) and providing a push and pull link connection I 2 between the lower end of the -lever .SiA and the agitator 'I at a vpoint between the ends thereof, 4at lor near the middle. In that way the lever 9 has a much vgreater mechanical advantage than where it operates the agitator from its pivotedend througha rshort crank arm, and it should be evident that va simpler and cheaper construction -is obtained. Thereis moreover no difficulty in regard to having the agitator sweep nearly the entire areaef the-screen 5, there vbeing suicient movementcfthe lower end ofthe lever 9 within thehandlel to movethe `agitatorfrom theone extremeA position shown `in- Fig. 2 to the other extreme position adjacent the diametrically opposite side of the casing. Due to the good mechanical advantage derived with lnyarrangement of the agitator l relative to: its operating lever 9,.the operator experiences no fatigue in ythe voperationlof the sifter,

.the lever 9 being operable like atrigger with very light 'finger pressure. .A leaf spring I 3 of inverted U form is provided betweenzthe upper end ofthe '.lever 9 and the upper end of the handle I0 and tends normally to urge vthe lever away from the handle so that the agitator 'I is adapted to be moved in one direction by finger pressure on the lever YSi and .to be returned by springv pressure.

The handle' Il) is formed from two strips 'of sheet metal Hi and Iriveted together'at i6. The

piece I5 .is U-shaped and has oppositely bent free ends -li riveted as at I3 to the wall of the casing 4 at the lower end thereof `The other handle'part I4 is generally of invertedV L.shape so as to provide `a substantially. horizontal portion I9, which has a downwardly projecting free end 2i) riveted to the wall of the casing. i at the upper end thereof, as at `2i The substantially vertical por.- tion 22 of the handle part I4 is curved longitudinallyjand also transverselmas shown, to ht the palmk of the hand oi theoperator. The lever 9 has its upper end forked to accommodate the curled end 24 of a smallsheet metal strap 25 that is soldered, welded, or otherwise suitablysecured to the bottom of the portion I9 Aof the'handlepart I4, the'curled end 2.4 of this vstrap providing a support for the pivot pin II, the separate ends `.of whichhavethe forked end '23 of the lever 9 bent around the same so as to support thelever S-"for pivotal movement in the handle, with'the lower end `260i .the lever movable betweenthe arms of the U-shaped bottoml part: 151501? -Lthe handle. The leaf spring I3 is retained in place by a lug 21 struck rearwardly from the lever 9 near the upper end thereof and projecting through a hole 28 provided in the adjacent end of the spring. The other end 29 of the spring is held against sidewise displacement relative to the handle by fitting in the trough of the transversely curved handle grip portion 22, as shown.

The agitato-r l is suitably stamped from a single piece of sheet metal to a generally ellipsoidal shape and has downwardly struck ribs 3S to ride on the screen 5. A longitudinal channel 3I is formed in the agitator, extending diametrically thereof, to accommodate a rod 32 which has an upwardly bent end providing the pivot 8. The rod 32 has its other end flattened, as indicated at 33, and projecting through a loop 34 struck upwardly from the end of the agitator, whereby to connect the end of the rod to the agitator. Lugs 35 struck upwardly from the other end of the agitator and bent over the adjacent end of the rod 32 serve to connect that end of the rod to the agitator. A sheet metal plate 3S curved to t the inside of the casing l is riveted Ain place, as indicated at 3l, and has a vertica1 rib 38 struck therefrom which accommodates Ythe upwardly bent end 8 of the rod 32 and forms a bearing therefor, closed at its upper end against entry of iiour, as clearly indicated in Fig. 3. An inverted U-shaped sheet metal strap 39 is soldered, welded, or otherwise suitably secured to the agitator 'I approximately at the middle of one side thereof and has a longitudinal slot 4D provided in the transverse portion thereof, in which the downwardly bent end il of a rod I2, forming rthe push and pull connection between the agitator and lever is entered. The downwardly bent end il has its extremity 42 bent at right angles to prevent accidental disconnection of the rod I2 from the agitator. The rod I2 extends freely through a hole t3 in the casing 4 and has its outer end 44 bent downwardy to provide an operating connection with the lower end 26 of the lever said lower end being bent U -shaped and having a hole ,f5.5 in the cross-portion of the U through which the rod I2 projects and another hole 6 in the lower arm of the U through which the bent end 45 of the rod projects. The'lower end 26 ofthe lever 9 is threaded onto the end 44 of the rod I2 before the lever is assembled in the handle IE. The same is true in regard to the agitator l, which must have the other end 4I of the rod I2 threaded through the slot 49 before the agitator is fastened in place by means of the plate 36,

In operation, when the lever S is pulled toward the handle grip portion of the handle Ill, the rod I2 moves with it and slides freely in the hole 33, the downwardly bent end 4I Vof the rod working in the slot il to provide a sliding pivotal connection between the rod and the agitator 1 to move the agitator in the same direction as the lever 9. When the lever 9 has been moved as far as it will go, finger pressure thereon is released and the spring i3 returns it to the position shown in Fig. l, thus returning the agitator I by means of the connection l2. The operation is smooth and comparatively quiet, and is so easy that the operator experiences no fatigue in the operation.

It is believed the foregoing description conveys a good understanding of the objects and advantages cf my'invention. The appended claims have been drawn to cover all legitimate modifications and adaptations.

I claim:

1. A sifter comprising a casing having a sifting screen in the bottom thereof, a vertically extending handle attached to one side of said casing, an elongated agitator pivotally mounted in said casing alongside the wall thereof at a point spaced appreciably from the yhandle circumferentially of the casing for oscillatory movement relative to the screen bottom toward and away from the lower portion of the handle, an operating lever for the agitator pivoted in the upperportion of the handle and having its lower portion movable relative to the lower portion of the handle in the oscillatory movement of said lever, the lower portion of said lever providing a perforated vertical portion above a perforated horizontal portion, and a rod slidable substantially horizontally through an opening provided therefor in the wall of the casing adjacent the lower portion of the handle and projecting through the perforation in the vertical portion of the lower end of said lever and having its end portion bent downwardly substantially at right angles and projecting through the perforation in the horizontal portion on the lower end of said lever, whereby said rod is movable with the lever in the oscillation thereof, the inner end portion of said rod being pivotally connected with the agitator at a point inter mediate the ends thereof, said lever vbeing movable manually in one direction and having spring means acting to move it in the opposite direction.

2. in a sifter, a casing having a sifting bottom, an agitator oscillatable relative to said bottom in said casing about a vertical pivot alongside the wall of said casing and above theV sifting bottom, a supporting handle for said casing, the pivot being spaced relative to the handle about circumferentially relative tothe casing, a trigger type operating lever pivoted on the handle, a spring normally tending to move the same in one direction, said lever being operable by hand in the opposite direction, and a push-and-pull rod guided for lineal movement in a Yhole provided in the wall of said casing above the sifting 'bottom and, pivotally attached at its outer end to said lever and having the inne-r end portion thereof bent substantiallyY vertically for a sliding pivotal connection in a slotprovided in the agitator', said slot extending transverselyrelative to the rod. y

3. A flour sifter comprising, in combination, a casing having a sifter bottom, va supporting handle for, said casing, an elongated agitator adapted to oscillate in said casing relative to the sifter bottom, means on the handle operatively connected vwith the agitator intermediateY the ends thereof to `transmit oscillatoryv movement to the agitator, and means for pivotally mounting said agitator at one end independently of the last mentioned means, said pivotaly mounting means comprising an upwardly extending, substantially vertical` `element on one end ofsaid agitator (parallelV to the side wall of the casing and in abutting relation, thereto, Yand a sheet metal bearing plate attached to the wall of said casing on the inner side thereof and Yhaving struck therefrom a generally channel-shaped, substantially verticaLjhollow bearing portion closed at its upper end and open at its lowerk end for reception of the pivotelement onA the agi,- tator, said bearing plate` being disposed in tight engagement with the inner'side of the wall of said casing to prevent entrance of flour behind the same, and the closed upper end of said bearing portion preventing entrance offlour therein` 4. In a sifter, a casing having an open top and a sifting bottom, a handle on one side of said casing, an elongated agitator pivotally mounted in said casing alongside the wall thereof at a point spaced appreciably from the handle circumferentially of the casing for oscillatory movement on top of the sifting bottom toward and away from the handle, a substantially vertically disposed operating lever outside the casing pivoted at its upper end in the handle for operation in a plane disposed substantially radially relative to the casing, and a substantially straight radially extending link disposed substantially horizontally in closely spaced substantially parallel relation to the top of the sifting bottom providing a push and pull connection between the lower end of said lever and the adjacent intermediate portion of the agitator through an opening provided in the lower portion of the intervening Wall of the casing above the sifting bottom, said lever being movable manually in one direction and having spring means acting to move it in the opposite direction.

5. In a sifter, a casing having an open top and a sifting bottom, a handle on one side of said casing, an elongated agitator pivotally mounted in said casing alongside the` wall thereof at a point spaced appreciably from the handle circumferentially of the casing for oscillatory movement on top of the sifting bottom toward and away from the handle, a substantially Vertically disposed operating lever outside the casing pivoted at its upper end in the handle for oscillatory movement relative thereto in a plane disposed substantially radially relative to the casing, and a substantially straight radially extending link reciprocable with the lower end of said lever and extending through an opening provided in the lower portion of the wall of said casing substantially horizontally in closely spaced substantially parallel relation to the top of the sifting bottom and slidably pivotally connected at its inner .end with the agitator at a point intermediate the ends thereof, the sliding movement of the link relative to the agitator being in a direction transversely relative to the link whereby the agitator is oscillated with the lever, said lever being movable manually in one direction and having spring means acting to move it in the opposite direction. y

ALBERT L. ZUCK. 

